Cooling system for fluids



April 17, 1962 1. VICTOR COOLING SYSTEM FOR FLUIDS 2 Sheets-Sheet 1Original Filed Aug. 29, 1955 fivvavrop Aemva Mara/Q April 17, 1962 I.VICTOR 3,029,612

COOLING SYSTEM FOR FLUIDS Original Filed Aug. 29, 1955 2 sh ts-sheet 2Ha f I WWW MM 3,629,612 Patented Apr. 17, 1962 3,029,612 COOLING YSTEMFOR FLUmS Irving Victor, Minneapolis, Minn, assignor to VicManufacturing Company, Minneapolis, Minn, a corporation of MinnesotaContinuation of abandoned application Ser. No. 531,198, Aug. 29, 1955.This application Apr. 25, 1960, Ser.

3 Claims. (Cl. 62-185) This invention relates toa cooling system forfluids. In general, it relates to a liquid cooling system wherein aprime fluid is cooled by a liquid, which, in turn, is cooled by arefrigeration system. More particularly, the inven tion is concernedwith maintaining solvents, used for cleansing garments and othermaterials, at a desired temperature.

The desirability of cooling fluids of all types has long beenrecognized. For example, one fluid cooling process to which thisinvention is applicable is the cooling of dry cleaning solvents. In theuse of solvents for cleansing garments and similar materials, it hasbeen a problem to maintain the solvent at its optimum temperature toobtain the best cleaning results. It is well known that if thistemperature becomes too high, bleeding of colors, shrinkage ofmaterials, and excessive solvent evaporation will result, while if thetemperature of the solvent is allowed to become too low, poor soilremoval will result. Maintenance of the solution temperature at apredetermined optimum point will produce good and efiicient results. Theprior practice has been to provide a solvent cooling heat exchangerthrough which cold water from the usual water supply is circulated.Obviously, such a system wastes a great deal'of Water and has no controlover the temperature of the cooling water flowing through the exchanger.

This application is a continuation of application Ser No. 531,198, filedAugust 29, 1955, now abandoned.

It is an object of this invention to provide a recirculating-liquid-typecooling system wherein the flow of a coolant for a heat exchanger iscontrolled by the heat given up by the fluid being cooled in the heatexchanger.

It is another object to provide a recirculating-liquidtype coolingsystem applicable for use with dry cleaning equipment to provide acoolant for circulation through a heat exchanger, whereby the coolingcapacity thereof will automatically be controlled in accordance with thetemperature of the dry cleaning solvent in order to maintain saidsolvent at its optimum temperature.

Other and further objects may become apparent from the followingspecification and claims, and in the appended drawings in which:

FIG. 1 is a rear elevational view of the improved liquid cooling system;

FIG. 2 is a left-side elevational view of said liquid cooling system;

FIG. 3 is a right-side elevational view of the refrigeration system;

FIG. 4 is a rear elevational view of said refrigeration system;

FIG. 5 is a diagrammatic view showing the liquid cooling system asconnected with a fluid heat exchanger; and

FIG. 6 is a vertical sectional view taken through the flow modulatingdevice.

Having reference to the several figuers of the drawings, the inventionwill now be described in detail.

Referring first to FIG. 5, reference numeral 10 indicates a'centrifugalpump-which is connected with an accumulation and expansion tank 11 bymeans of a pipe 12. The pump 10 is capable of delivering the water, orother suitable liquid coolant, received from said tank 11 under asubstantial pressure to a chiller tank 13 through a pipe 14. A suitablecooling coil is disposed within the tank 13 and will be subsequentlydescribed in connection with the description of the refrigerationsystem. From chiller tank 13, the cold water is delivered through adischarge pipe 15 and outwardly therefrom to a heat exchanger 16 throughwhich dry cleaning solvent, or the like, is flowing under the control ofvalves 16a and 16b. In order to maintain the temperature of the waterflowing from the heat exchanger 16 at a predetermined point, said heatexchanger' is connected by heat exchanger discharge pipe 17 to anextremely simple, yet highly efiicient thermostatically controlled flowmodulating device 18. Said flow modulating device is provided to controlthe flow of water from heat exchanger 16 back to the accumulation andexpansion tank 11. Obviously, when the temperature of the water in theheat exchanger discharge pipe 17 is sufiiciently low, and therefore, thevalve 18 is at least partially closed, the pressure in the dischargepipe 15 will be increased because of the action of pump 10. A pressureresponsive release valve 19 is interposed in a bypass pipe 20 connecteddirectly between the discharge pipe 15 and the accumulation tank 11, sothat when the pressure in line 15 increases to a predetermined limit,the relief valve 19 will open to the extent necessary to relieve saidpressure, and a portion of the water will be permitted to flow directlyto the tank 11 through pipe 21} without passing through the heatexchanger 16. Thus, the flow through heat exchanger 16 is limited, andcontinuous circulation of water is maintained through chiller tank 13.

Details of the flow modulating device 18 are best shown in FIG. 6. Saiddevice has a main body or casing 18a with a chamber 18b definedtherewithin. The casing contains an inlet port connected with the heatexchanger discharge pipe 17 by the flanged coupling assembly 21. Withinthe valve chamber 18b adjacent the inlet port is mounted a valve unitcomposed of a closure disc 18c against which the flanged coupling 21sealingly engages. Said disc is imperforate except for a valve seat 18dformed therethrough and said seat is normally closed by a valve element1 8e, which is norm-ally seated therein. A valve stem 18 is connectedwith the valve element 18a in a fixed relation thereto and has a springpressed collar 18g fixed to the upper portion thereof and is normallyheld in a closed position by a spring 18h interposed between the collarand the disc 180. A temperature responsive thermostatic element 18i iscarried by a supporting cage 18k that actuates a push rod 181 to projectthe same downwardly in accordance with increases in the temperature ofthe liquid being controlled, and in the present form, in accordance withthe temperature of the liquid in chamber 18b. The push rod 181 isadjustably spaced above the upper end of valve stem 18 so that a lostmotion connection is provided therebetween. The spacing between thesetwo elements is adjustably varied by the adjustment rod 22, which isscrew threaded through the upper portion of the casing 18a, and isprovided with a handle 22a that may be pre-set with respect to an index2211 on the surface of the casing 18 When the rod 22 is projecteddownwardly, the valve will open at a lower temperature, and when thesame is projected upwardly to increase the spacing between the push rod181 and the valve stem 18 the valve will begin to open at a highertemperature. A resilient member, such as the resilient sleeve element18m, normally holds the thermostatic element upwardly against the lowerend of the adjustment rod 22. In order to permit a continuous restritcedflow of the liquid to be controlled to contact the sensing element 181',a by-pass conduit 23 offers communication directly between the heatexchanger discharge pipe 17 and 3 i the valve chamber 1811. A needlevalve 24 is' provide to adjust the flow through the by-pass conduit 23.Liquid from the chamber 18b is connected by a return conduit 25 to tank11 and back therefrom to the inlet opening of pump 10 through pipe 12. Athermometer 26 may be mounted in conduit 25 to indicate the temperaturein the return flow liquid. The recirculating-liquid cooling system isshown in FIGS. 1 and 2.

The refrigeration system for cooling the water in the chiller tank 13 isillustrated in FIGS. 3 and 4. A compressor 40 has its high pressure sidejoined to a pipe 41 into the condenser assembly, which consists of apair of condenser units 42a and 42b, which are designed to provide aminimum of flow restriction of the fluid therethrough during the coolingof the refrigerant. Doubling the size of the condenser capacity overthat conventionally used with a particular size compressor materiallyincreases the efficiency of the cooling apparatus. The condensedrefrigerant passes through the condensers and into a receiver 43, andupwardly therefrom to a filter dryer unit 44 of conventional design, andthereafter the pipe from said unit 44 delivers the dry refrigerant intoa counter-ilow heat inter-changer chamber defined by tubular jacket 45concentrically surrounding a portion of the suction line 46 from thecoil within the chiller tank 13. A thermostatic expansion valve 47controls the flow of refrigerant from the heat interchanger 45 and intoan evaporator coil disposed within the chiller shell of tank 13.Obviously, the cold gas coming from the evaporator coil within the tank13 through suction line 46 serves to cool the condensed liquid passingthrough the heat interchanger 45 to permit highly efficient coolingthrough the coil within the tank 13. Also, the suction gas coming fromthe coil through suction line 46 is warmed sufliciently to positivelyinsure evaporation of any liquid therein to permit efficient compressionthereof by the compressor 49. A limit switchtype of shut-E 48, having asensing bulb 48a (best seen in FIGS. 1 and 2) disposed adjacent thewater discharge line 15 from the chiller tmk, is provided to preventsaid water from becoming too cold when insufficient heat is beingsupplied thereto by the heat exchanger 16. Limit switch 48 is connectedwith the compressor motor and condenser fan motor (not shown) inconventional way, and merely shuts off the motor. The motor a of pump10, however, is not shut off by limit switch 48, but is constantly andcontinuously driven to circulate liquid through the chiller tank 13 andheat exchanger 16 in accordance with the demands of the flow modulatingdevice 18.

The general operation of the process and apparatus is as follows: Asseen in FIG. 5, the fluid to be cooled, as for example, a dry cleaningsolvent which is to be maintained at a predetermined optimumtemperature, is circulated from a cleaning machine, not shown, throughheat exchanger 16 under the control of valves 16a and 16b.

The coolant, water or other suitable liquid, is circulated by pump 10from tank 11 through pipe 12 and thence to chiller tank 13 by way ofpipe 14. The coolant then circulates through discharge pipe 15 into theheat exchanger 16 and out of heat exchanger discharge pipe 17 to theflow modulating device 18. The conduit 23, seen in FIG. 6, equipped witha manually operable needle valve 24 extends from pipe 17 directly tovalve chamber 18b to form an adjustable by-pass around the elements 18dand 18a to allow a controlled flow of liquid into contact with thethermostatic element 18in When a demand for the cooling capacity of theheat exchanger 16 exists, and therefore, the temperature of the coolantflowing into heat exchanger discharge pipe 17 is above a predeterminedpoint, thermostatic element 18i will react in response to thetemperature, of the limited amount of coolant passing into chamber 1811by way of conduit 23. Valve element 18a is pushed downward allowing flowthrough 18d 'into the valve chamber 18b,

and thence through pipe 25 back to the accumulation and expansion tank11.

When there is no demand for the cooling capacity of the heat exchanger,and therefore, the temperature of the coolant flowing through the flowmodulating device 18 becomes lower than the predetermined point,thermostatic element 18: will react in response to the temperature ofthe coolant flowing through the modulating valve. Valve element 18cmoves upward and positions itself within valve seat 18d to terminate theflow through the valve. As flow through the modulating valve 18 isterminated, or substantially reduced, pressure builds up in the chillerdischarge pipe 15 due to the action of pump 10. The pressure responsiverelief valve 19 will open at a predetermined pressure and allow coolantto by-pass the heat exchanger 16 and flow through pipe 20 back to theaccumulation and expansion tank 11.

The flow modulating device 18, working in conjunction with pressurerelease valve 19, permits very accurate control of the temperature ofthe discharge coolant from the heat exchanger 16. This temperature maybe predetermined by simply pre-setting the manually adjustable handle22a'with the index 22b. The adjustment of the sensing by-pass 23 isimportant in maintaining the temperature and pressure control, sinceonly sufiicient cool-ant should be permitted to flow around controlvalve 184: to permit accurate sensing thereof by the thermostaticsensing element 18L 7 Excessive flow through by-pass 23 will produceexcessive circulation through heat exchanger 16 even when the modulatingvalve itself is closed, thus providing too much cooling in the heatexchanger and preventing the optimum temperature for the cleaning solu--'tion from being maintained. Needle valve 24 may be moved to a fullyopen position to allow by-pass conduit 23 and said valve to be easilyflushed free of any foreign material, such as pipe scale or the like.Flow through the flow modulating device may be terminated by movingneedle valve 24 to its closed position and adjusting the handle 22a sothat valve'element 18c moves to a closed position with respect to valveseat 18d.

As has been brought out previously herein, this invention provides acooling system which requires the use of only the initial supply ofcoolant liquid thereto, and does not constantly use a supply of coolant,such as water from a city water supply or the like, and thereaftermerely discharge this cooling water down the drain. By providing arecirculating-liquid-type coolant system wherein the coolant liquid isconstantly maintained at an accurately controlled temperature, there isno waste of the coolant liquid and a great deal better control of thecoolant temperature can be obtained by the refrigeration system. In

addition, by maintaining continuous circulation of the coolant liquidthrough the chiller tank 13, a constant temperature for the entirevolume of coolant is thus obtained, thus building up a reservoir ofcooling capacity within the system which would not be possible withoutthe continuous circulation arrangement.

As changes and modifications may be apparent to those skilled in theart, this invention is defined in terms of the appended claims.

I claim:

1. A heat exchange system, comprising a liquid circuit, a first heatexchanger in said circunit adapted to reduce the temperature of acoolant liquid in said circuit, a second heat exchanger in said circuiton the discharge Side of said first heat exchanger adapted to reduce thetemperature of a medium to be refrigerated, a modulating valveresponsive to the temperature of liquid passing therethrough disposed insaid circuit between the discharge side of said second heat exchangerand the intake sideof said first heat exchanger for controlling theflow. of coolant liquid in said second heat exchanger, a pressure reliefvalveoperatively disposed in said circuit between the discharge andintake side of said first heat exchanger forming a by-pass about saidsecond heat exchanger and said modulating valve, a pump disposed in saidcircuit capable of circulating the coolant liquid under sufiicientpressure to maintain a substantial circulation of the coolant liquidwithin said circuit through said pressure relase valve when flow throughsaid modulating valve is restricted.

2. A heat exchange system, comprising a liquid circuit, a liquid chillerdisposed in said circuit, -a pump capable of delivering substantialpressure disposed within said circuit with its high pressure sideconnected to said chiller, a heat exchanger disposed within said circuiton the discharge side of said chiller, an expansion tank disposed insaid circuit between the discharge side of said heat exchanger and thelow pressure side of said pump, a modulating valve responsive to thetemperature of liquid passing therethrough disposed in said circuitbetween said heat exchanger and said expansion tank, and adapted tocontrol the rate of flow of liquid through said heat exchanger, and apressure responsive bypass valve disposed in said circuit between thedischarge of said chiller and said expansion tank.

3. A heat exchange system, comprising a liquid circuit, a first heatexchanger in said circuit adapted to change the temperature of theliquid in said circuit, a second heat exchanger in said circuit on thedischarge side of said first heat exchanger adapted to change thetemperature of a medium to accord with the temperature of the liquid insaid circuit, a pump capable of imparting a substantial pressure to theliquid in said circuit, a pressure release valve in said circuit betweenthe discharge and intake sides of said first heat exchanger forming aby-pass about said second heat exchanger, a modulating device in saidcircuit on the discharge side of said second heat exchanger embodying acasing containing a valve adapted to terminate flow through said secondheat exchanger, a thermal element in said casing on the discharge sideof said valve operatively controlling said valve, and a manuallyoperable by-pass associated with said casing for by-passing liquid insaid circuit about said valve and into contact with said thermalelement.

References Cited in the file of this patent UNITED STATES PATENTS1,850,963 Sponar Mar. 22, 1932 1,877,510 Hughes Sept. 10, 1932 2, 25,228Cornelius July 27, 1943 ,336,066 Cain Dec. 7, 1943

